Interesting one. I've read that left-handers in about 50% of cases have completely different brain organizations (the other 50% they are a mirror image of righthanders). That's actually why they're often excluded from
It would be interesting to see if this is an actual factor in personality theory or if it's an independent factor.
I think I'm naturally right handed. Nerve damage on my right side, though, can make it hard to move my arm, so I write with my left hand, too - just as easily as with my right. I also have played piano since age 3, so that might have another thing to do with it.
INTJ, mix-handed (next best thing to being ambidextrous). I write with my right hand, but I do lots of other things in left-handed configuration, including but not limited to shooting (due to left-eye dominance), billiards (can't shoot pool right-handed to save my life), and most tool-related tasks (including but not limited to hammering nails).
I was originally left-handed, but was reprogrammed by "the system" (when I was in elementary school) to write with my right hand, as was customary in the '80s, but only for the sake of expediency (as opposed to superstition as it was generations ago). It's since been proven that "reprogramming" a person's natural hand preference causes or exacerbates learning deficiencies.
ISFP - Ambidextrous. I can write with both my left hand and right hand but my dominant writing hand is the left one. I eat with my right hand. Use a pair of scissors with my right hand. I play badminton with both hands except for baseball which I can only play left-handed.